David Hughes is the Daily Telegraph's chief leader writer. He has been covering British politics for 30 years.

What's the point of solar panels?

Another inconvenient truth for global warm-mongers emerges in this report on the complete and utter uselessness of solar panels.

Solar panels: a bit of a waste of time?

According to the Royal Institution of Chartered Surveyors – who can hardly be dismissed as a bunch of raving climate change counter-revolutionaries – bolting a solar panel to your roof at a cost of Â£5000 or so will never, ever repay the outlay. It would take as long as 200 years to cover the cost in saved energy, yet the panels would last no more than 30 years. In contrast, putting in decent loft and wall insulation would pay for itself in just three years.

This makes the point once again that the real key to lowering carbon dependency is not sticking fancy kit on your roof – is David Cameron's famous wind turbine generating enough juice to fire up his electric toothbrush? – but taking low-cost energy conservation measures. Unexciting, but true.

If every building in the country was properly insulated, our carbon emissions would plummet.

But do they need to? Christopher Booker has rattled the bars of climate change campaigners by questioning the scientific validity of their claims on global warming, arguing that the Intergovernmental Panel on Climate Change has cynically manipulated scientific evidence.